bells and whistles
From Longman Business Dictionarybells and whistlesˌbells and ˈwhistles noun [plural]MARKETING extra things that are offered with a product or system to make it more attractive to buyersFax systems on the market today offer bells and whistles such as answering-machine capability.The basic rule about computer memory is this: Buy as much as you can afford, even if it means sacrificing other bells and whistles.